In-liquid fluorescence detection device and method of detecting fluorescence in liquid

Abstract

To provide an in-liquid fluorescence detection device capable of accurately detecting fluorescence in a liquid. An in-liquid fluorescence detection device includes a light source emitting an excitation light having a wavelength in which Raman scattered light is generated in a liquid in a wavelength band between first and second fluorescence wavelength bands toward the liquid, which can contain a first substance that emits light having higher intensities in the first fluorescence wavelength band as compared with in the second fluorescence wavelength band and a second substance that emits light having higher intensities in the second fluorescence wavelength band as compared with in the first fluorescence wavelength band; and a fluorescence detection unit detecting light in the first and second fluorescence wavelength bands.

1 . An in-liquid fluorescence detection device, comprising:
 a light source emitting an excitation light having a wavelength in which Raman scattered light is generated in a liquid in a wavelength band between first and second fluorescence wavelength bands toward the liquid; and   a fluorescence detection unit detecting light in the first and second fluorescence wavelength bands to determine a presence in the liquid of a first substance, which emits light having higher intensities in the first fluorescence wavelength band as compared with in the second fluorescence wavelength band, and a second substance, which emits light having higher intensities in the second fluorescence wavelength band as compared with in the first fluorescence wavelength band.   
     
     
         2 . The in-liquid fluorescence detection device according to  claim 1 , further comprising:
 a comparison unit comparing an intensity of the detected light in the first fluorescence wavelength band with an intensity of the detected light in the second fluorescence wavelength band.   
     
     
         3 . The in-liquid fluorescence detection device according to  claim 2 , further comprising:
 a fluorescence reference determination unit determining that the liquid contains the first substance when the intensity of the detected light in the first fluorescence wavelength band is higher than the intensity of the detected light in the second fluorescence wavelength band, and determining that the liquid contains the second substance when the intensity of the detected light in the second fluorescence wavelength band is higher than the intensity of the detected light in the first fluorescence wavelength band.   
     
     
         4 . The in-liquid fluorescence detection device according to  claim 1 ,
 wherein the first substance is a biotic particle and the second substance is an abiotic particle.   
     
     
         5 . The in-liquid fluorescence detection device according to  claim 4 ,
 wherein the first fluorescence wavelength band is positioned on a longer wavelength side than the second fluorescence wavelength band.   
     
     
         6 . The in-liquid fluorescence detection device according to  claim 4 ,
 wherein an intensity of autofluorescence emitted by the biotic particle in the first fluorescence wavelength band is higher than that of autofluorescence emitted by the abiotic particle in the first fluorescence wavelength band, and   an intensity of autofluorescence emitted by the abiotic particle in the second fluorescence wavelength band is higher than that of autofluorescence emitted by the biotic particle in the second fluorescence wavelength band.   
     
     
         7 . The in-liquid fluorescence detection device according to  claim 1 ,
 wherein the first and second substances are abiotic particles.   
     
     
         8 . The in-liquid fluorescence detection device according to  claim 1 ,
 wherein at least one of the first and second substances is a fluorescent substance dissolved in the liquid.   
     
     
         9 . The in-liquid fluorescence detection device according to  claim 1 , further comprising:
 a scattering light detection unit detecting scattering light having a same wavelength as the excitation light that is generated in the liquid irradiated with the excitation light.   
     
     
         10 . A method of detecting fluorescence in a liquid comprising the steps of:
 emitting an excitation light having a wavelength in which Raman scattered light is generated in a liquid in a wavelength band between first and second fluorescence wavelength bands toward the liquid; and   detecting light in the first and second fluorescence wavelength bands to determine a presence in the liquid of a first substance, which emits light having higher intensities in the first fluorescence wavelength band as compared with in the second fluorescence wavelength band, and a second substance, which emits light having higher intensities in the second fluorescence wavelength band as compared with in the first fluorescence wavelength band.   
     
     
         11 . The method of detecting fluorescence in the liquid according to  claim 10 , further comprising the step of:
 comparing an intensity of the detected light in the first fluorescence wavelength band with an intensity of the detected light in the second fluorescence wavelength band.   
     
     
         12 . The method of detecting fluorescence in the liquid according to  claim 11 , further comprising the steps of:
 determining that the liquid contains the first substance when the intensity of the detected light in the first fluorescence wavelength band is higher than the intensity of the detected light in the second fluorescence wavelength band; and   determining that the liquid contains the second substance when the intensity of the detected light in the second fluorescence wavelength band is higher than the intensity of the detected light in the first fluorescence wavelength band.   
     
     
         13 . The method of detecting fluorescence in the liquid according to  claim 10 ,
 wherein the first substance is a biotic particle and the second substance is an abiotic particle.   
     
     
         14 . The method of detecting fluorescence in the liquid according to  claim 13 ,
 wherein the first fluorescence wavelength band is positioned on a longer wavelength side than the second fluorescence wavelength band.   
     
     
         15 . The method of detecting fluorescence in the liquid according to  claim 13 ,
 wherein an intensity of autofluorescence emitted by the biotic particle in the first fluorescence wavelength band is higher than that of autofluorescence emitted by the abiotic particle in the first fluorescence wavelength band, and   an intensity of autofluorescence emitted by the abiotic particle in the second fluorescence wavelength band is higher than that of autofluorescence emitted by the biotic particle in the second fluorescence wavelength band.   
     
     
         16 . The method of detecting fluorescence in the liquid according to  claim 10 ,
 wherein the first and second substances are abiotic particles.   
     
     
         17 . The method of detecting fluorescence in the liquid according to  claim 10 ,
 wherein at least one of the first and second substances is a fluorescent substance dissolved in the liquid.   
     
     
         18 . The method of detecting fluorescence in the liquid according to  claim 10 , further comprising the step of:
 detecting scattering light having a same wavelength as the excitation light that is generated in the liquid irradiated with the excitation light.